Holster for a gun magazine



FIG. 1 is a perspective view of a holster for a gun magazine in accordance with my new design;

FIG. 2 is a left side view thereof, the right side being a mirror image;

FIG. 3 is a front view thereof;

FIG. 4 is a top view thereof;

FIG. 5 is a rear view thereof; and,

FIG. 6 is a bottom view thereof.

The broken lines immediately adjacent the shaded areas represent the bounds of the claim, and all other broken lines are for illustrative purposes only. None of the broken lines form a part of the claimed design. 

The ornamental design for a holster for a gun magazine, as shown and described. 